Sens’o sensor


Declaration of conformity

Download the declaration of conformity


The Sens’o is LoRaWAN class A sensor, it uses a disposable A 3.6V battery as power supply.

Sens’O detects each watermeter turn (maximum disk rotation speed: 0.87 revolutions per second).

Sens’O device measures consumption index and detects alerts such as leakage, fraud, back siphoning, low battery or risk of freezing.



Family code

The family code of Sens’o sensors is: 50-70-011-xxx

Installation and use


To Start-up the device, it is necessary to remove the plastic cover and protective film from foam seal. Foam seal is bonded on the transparent plastic piece under device.

Sens’o device is Arad’s watermeter compatible, it must have a half golden disk.

The sensor must be fixed on watermeter. Each turn means watermeter has detected the consumption of one liter.

To complete installation and to begin radio transmission, the watermeter must count more than 10 liters. For each disk turn, the red led blinks one time.

After checking that the installation is complete, a plastic pin must be inserted into Sens’O and the watermeter.  This plastic pin locks mechanical installation. Don’t forget to remove small tab by hand or by pliers, it prevents fraud by user.



Dimension: 97 x 75 x 105.5 mm (except fixing hook)

Combustion behavior: UL94HB

Storage temperature: -30°C -> +60°C

Ingress protection: IP68 1 month@1m

Watermeter Index

To read the index precisely, you must record each register. The less significant register is in dL (Graduations around the disk).


Propagation radio

In order for the sensor to function correctly, it is better to limit the number of obstacles in order to avoid excessive attenuation of the radio wave.


The information in the table below represents how long the battery can last. It is  based on the default configuration at ambient temperature (+25°C) within the optimal use of the sensor throught LoRaWAN network (one uplink frame), and when  the spreading factor used is SF12.

The capacity of the disposable battery is 3.6Ah, 85% of it is used.

Transmission periodicityBattery life
1 frames/24 hours+15 years

Human Machine Interface

There is one red led on the Sens’o device.

After installing the device, it detects the presence of watermeter disk after few seconds, the red led blinks 10 times.

Applicative layer

The Sens’o device implements “volume meter” and “senso” clusters.

The Sens’o device integrates clusters:

ClusterCluster name Managed attributes
0x8002Volume meterAll

Default configuration

A default configuration is set:

  • The device reports a batch every 24 hours, including the Volume, the MinFlow and the MaxFlow of the “Volume Meter” cluster, and the Status of the“Senso” cluster.

The following settings have been used to configure the batch:

AttributeTag sizeTag labelResolutionSample type
Volume 31111 (ST_l32)
MinFlow215 (ST_l8)
MaxFlow315 (ST_l8)
Status014 (ST_U8)

To decode the batch report, based on these parameters, it is necessary to use br_uncompress as below:

echo « …. » | ./br_uncompress -a 3 0,1,4 1,1,11 2,1,5 3,1,5

  • Another report is configured on the Status of the “Senso” cluster, as soon as the status changes.

The field bit of the Status is described as follow:

Bit numberDescription
1Back water level 1
2Back water level 2
3Back water level 3

Every change on the default configuration must respect the legal duty cycle. (For example the most restrictive in EU is 0.1%, so in SF12 it is around 1 frame each hour)

Frame examples

Standard report



Report of the volume index

→Applicative payload is: 11 0a 80 02 00 00 2b 00 00 00 1d

00 00 00 1d: volume value (29)

Report of the status of the sensor

→Applicative payload is: 11 0a 80 03 00 00 18 60

60: Status of the sensor (Battery and Installation OK: 0b01100000)



Configure a standard report on the volume meter

Report the volume on a variation of 25dl. The status has to be reported at less each 24 minutes, and a minimal timing of 5 minutes between 2 reports has to be settled.

→Applicative payload is: 11 06 80 02 00 00 00 2b 80 05 05 a0 00 00 00 19

80 05: minimum reporting change (5 minutes)

05 a0: maximum reporting change (24 minutes)

00 00 00 19: reportable change (volume value: 25dl)

To disable the previous configuration, change the value of the minimum and maximum sending interval and the delta to 0: 11 06 80 02 00 00 00 2b 00 00 00 00 00 00 00 00

Batch report



Change the default configuration to send batch each hour with one index of volume

The default Tag Label is 1 and Tage Size is 3 for Volume. So the frame to send is:

11 06 80 02 1D 00 00 00 80 0C 80 3C 00 00 00 00 00 00 00 01 0B

80 0C: minimum reporting interval (1 hour)

80 3C: maximum reporting interval (1 hour)

00 00 00 00: required delta value (size: 4 bytes for attribute Volume => attribute type = 2b)

00 00 00 01: required resolution

0B: tag value (ob00001011 => 00001: tag label, 011: tag size)

→Response: 11 07 80 02 00 00 00[/expand]

Configure a batch report on volume meter and voltage battery:

Timestamp and record the volume meter with a resolution of 1, a value has to be saved at each incrementation of the index. Timestamp and record the battery voltage with a resolution of 0.1V, a value has to be saved at least all the 24 hours. All recorded datas have to be concatenated and sent at maximum every hour.

 →For the Volume Meter the delta has to be set to 0x00000001, minimum to 0x0000, the maximum to 0x803c , the resolution to 0x00000001  and the tag to 0x01 (size 1 and label 0). The cluster to report is 0x8003 and the attribut 0x0000 (Volume).

For Disposable Battery power voltage the delta has to be set to 0x0064, minimum to 0x800a, the maximum to 0x85A0, the resolution to 0x0064, the tag to 0x09 (size 1 and label 1), the field to 0x04. The cluster to report is 0x0050 and the attribut 0x0006 (Node power descriptor).

There are two different measures to record in the batch, so the tag size has to be 1. Label 0 can be used for volume meter and label 1 for the level of rechargeable battery.

It is necessary to send two frames to configure this batch.

Number of labelTag labelTag size
1 or 20/11
3 or 400/01/11/102
5 or 6 or 7 or 8000/001/010/011/100/101/110/1113

Applicative payload of the volume meter

11 06 80 02 1D 00 00 00 00 00 80 3C 00 00 00 01 00 00 00 01 01

1D: 0b00011101 => 0001110: size of configuration string after attribute ID (14 bytes)

00 00: minimum reporting interval (0 seconds)

80 3C: maximum reporting interval (1 hour)

00 00 00 01: required delta value (size: 4 bytes for attribute Volume => attribute type = 2b)

00 00 00 01: required resolution

01: tag value (ob00000001 => 00000: tag label, 001: tag size)

→Response: 11 07 80 02 00 00 00

Applicative payload of the battery voltage

11 06 00 50 15 00 06 04 80 0a 85 a0 00 64 00 64 09

15: 0b00010101 => 0001010: size of configuration string after attribute ID (10 bytes)

04: index of required field (disposeable battery)

80 0a :minimum reporting interval (10 minutes)

85 a0: maximum reporting interval (24 hours)

00 64: required delta value (size: 2 bytes for attribute NodePowerDescriptor  => attribute type = 41, 0.1V)

00 64: required resolution (0.1V)

09: tag value (ob00001001 => 00001: tag label, 001: tag size)

→Response: 11 07 00 50 00 01 00 06

To decode the batch reception, use the br_uncompress. Type for Volume Meter is I32 (11) and for the battery power type is U16 (6), so it is necessary to use this command:

echo « 26150020e06001d71e0000a0650f » | ./br_uncompress -a 1 0,1,11 1,100,6



cnt: 5                       # Counter of the batch (from 0 to 7)

263                         # Timestamp in second of sending of the frame

# Format of data is: TimeStamp of Measure | Label | Value

263 0 45                # TimeStamp: 841 s       Label 0: Volume Meter             Value: 45

263 1 3000            # TimeStamp: 811 s        Label 1: battery                        Value: 3.0 V

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